Package for fragile articles



Feb. 3, 1970 B. EDwARDg 3,493,164

PACKAGE FOR FRAGILE ARTICLES Filed Feb. 1968 4 Sheets-Sheet 1 His Art'ys Feb. 3, 1970 a. EVDWARDS PACKAGE FOR FRAGILE ARTICLES Filed Fb. 9, 1968 4 Sheets-Sheet 2 Ill HHIIHHIHIHHIIIllIHHHHIIIHWWHHI HHIHIIHIIHHIHIHIIIHIHHHHIHI I hvvEv-mR. Bryanf Edwards 38b 380 52 ,11

His An s F ch. 3, 1970 B. EDWARDS 3,493,164 PACKAGE FOR FRAGILE ARTICLES Filed Feb. 9, 1968 4 Sheets-Sheet 3 INVEY'IOR. Bryan) Edwards His AH'ys Feb.'3, 1970 EDWARDS' 3,493,164 I ACKAGE F R Filed Feb. 9, 1968 4 Sheets-Sheet 4 V Bryon) Edwards United States Patent 3,493,164 PACKAGE FOR FRAGILE ARTICLES Bryant Edwards, Clarendon Hills, 111., assignor to Illinois Tool Works Inc, Chicago, 11]., a corporation of Delaware Filed Feb. 9, 1968, Ser. No. 704,450 Int. Cl. B65d 85/32 US. Cl. 229-25 22 Claims ABSTRACT OF THE DISCLOSURE The present invention is generally directed to a package for fragile articles, and has particular utility as an egg carton or package although many other types of fragile articles or objects may also be packaged in the manner contemplated herein. In the discussion that is to follow, the present invention will be discussed generally in relation to the packaging of eggs, it being understood, of course, that the invention is not limited to eggs only, but encompasses the packaging of any fragile article or object.

Multi-cell packages for fragile articles such as eggs and the like are well known. These packages must meet certain minimum industry accepted standards which have been developed over the years, In the packaging of eggs, for example, the packages must be economical, capable of being nested and freely separated, capable of being handled and filled by high speed packaging equipment, able to withstand impact forces normally encountered in shipping and handling, easy to open and capable of being re-used.

Prior to the introduction of thermoplastic materials, egg packages were customarily made by two different techniques. The most popular technique from the standpoint of its commercialization has been the one or two-piece paper fiber cartons molded or formed by some type of pulp forming process. The other technique involved the fabrication of a multi-piece carton formed from fiat paperboard sheets where such sheets are bent, slit or otherwise shaped to approximate the contour of the molded fiber carton. It will be apparent that many of the limitations of shape and contour necessary in a paperboard sheet carton are eliminated by molded fiber cartons which may be shaped, within limits, to meet any article contour which may be desired.

While molded fiber and paperboard sheet cartons have served the egg packaging industry well for a number of years, certain aspects have either been overlooked or are incapable of solution because of inherent limitations. Cushioning of eggs during shipping and handling can be improved to avoid breakage of eggs which, because of the absorbent character of the molded fiber or paperboard sheet cartons fuses the eggs to the carton and makes the cartons undesirable to use insofar as the ultimate consumer is concerned. The ability to view the eggs in the package is a very desirable aspect, and at the same time, it is preferable that the egg cartons have a tamperproof aspect to prevent consumers from opening the package and leaving it opened. In molded fiber and paperboard sheet cartons, the packages must be opened in order to view the eggs, and this of necessity, destroys any tamperproof aspect which might be incorporated in the egg carton.

3,493,164 Patented Feb. 3, 1970 When the egg package has been opened, the eggs have not generally been protected from breakage for the full height of the eggs and at the same time exposed for easy removal thereof by the ultimate consumer. The present invention relates to the above and other aspects as will become apparent.

In recent years, various types of thermoplastic materials have been developed and are being used in the egg packaging industry. For example, expanded polystyrene material has been used as a substitute for paper fibers employed in the molded fiber cartons; however, this substitution of material does not overcome the limitations noted above. Various types of thermoformed or injection molded compartmented plastic trays have been used in combination with cardboard sleeves, shrink film overwraps, and the like, but none of these packages have met the minimum accepted industry standards set forth above and have additionally overcome the inherent limitations in a molded fiber or paperboard sheet carton,

The present invention is not only designed to meet the minimum accepted standards in the egg packaging industry, but also provides significant improvements in the construction of the package which overcomes the above mentioned limitations, and as a result, provides a more effective package for the egg processer, grocery store owner, and ultimate consumer.

It is the principal object of the present invention to provide a new and improved package for fragile articles.

Another object of the present invention is the provision of a package for fragile articles which adequately protects the articles against breakage or damage during shipping or handling while exposing the articles for easy removal thereof.

A further object of the present invention is to provide a package for fragile articles which offers substantial lateral and vertical rigidity, and at the same time can resist bending or twisting thereof.

Still another object of the present invention is the provision of a package for fragile articles in which the articles may be viewed Without opening the package, the package also preferably having tamperproof features which make it difiicult or embarrassing to o en the package and leave it open.

A still further object of the present invention is to provide a package for fragile articles including a deep drawn nestable section which is at least partially collapsible to reduce the overall dimensions of the package to conform the package to generally the same size as those existing commercial packages, and at the same time, is capable of maintaining a lid element in a taut condi tion to prevent wrinkling thereof.

Other and further objects and advantages include the provision of a package for fragile articles which is economical, easy to manufacture, pleasing in appearance, leak-proof, not affected by moisture, sanitary, lightweight, easy to handle, capable of being stacked without jamming or incurring damage thereto, and is otherwise well adapted for the purposes intended.

The foregoing, and other objects and advantages will be more apparent from the following detailed description When considered in connection with the accompanying drawings wherein:

FIG. 1 is a perspective view of the egg supporting or elongated compartmented tray section which is constructed in accordance with the principles of the present invention, and illustrating the manner in which eggs are positioned in the tray section;

FIG. 2 is a top plan view of the enlo-ngated compartmented tray section only which is depicted in FIG. 1;

FIG. 3 is an enlarged vertical sectional view as viewed along line 3-3 of FIG. 1, which depicts the manner in which eggs or other fragile articles are axially supported thereby;

FIGS. 4-6 are enlarged vertical sectional views similar to FIG. 3 and illustrating the manner in which eggs are cushioned at various stages of movement when subjected to drop impact forces and the like;

FIG. 7 is an enlarged fragmentary sectional view similar to FIGS. 3-6, but showing a slightly modified form of axial cushioning means;

FIG. 8 is an end elevational view of the eggs and tray section depicted in FIG. 1;

FIG. 9 is a fragmentary side elevational view of the eggs and tray section depicted in FIG. 1;

FIG. 10 is a fragmentary top plan view of the eggs and tray section depicted in FIG. 1, and illustrating in connection with FIGS. 8-9 the manner in which the eggs are cushioned against lateral shock forces and the like;

FIG. 11 is an enlarged end elevational view, partly in section, of a plurality of similarly configured tray sections telescopically received one within the other in stacked relationship.

FIG. 12 is an exploded end elevational view of a tray section and a cover section having cooperating fastening means which secure the parts to one another;

FIG. 13 is an end elevational view of the tray section and cover section shown in FIG. 12 with the parts in assembled relationship;

FIG. 14 is an end elevational view of a tray section and cover section which are shown as being heat sealed to one another;

FIG. 15 is an end elevational view similar to FIG. 14, and illustrating the manner in which the cover section can be removed from the tray section;

FIG. 16 is a top plan view of a cover section and tray section, the cover section having perforated impression which facilitates removal of the inner portions of the cover section from the remainder of the cover section and tray section;

FIG. 17 is a fragmentary top plan view of a tray section which is capable of being radially collapsed;

FIG. 18 is a fragmentary top plan view showing the manner in which the tray section shown in FIG. 17 can be collapsed from the dotted to the full line position shown;

FIG. 19 is an end elevational view illustrating the manner in which the tray section can be collapsed from the dotted to the full line position which is depicted;

FIG. 20 is a side elevational view of a plurality of egg cartons stacked one above the other in a plurality of tiers of three cartons or containers in each tier; and

FIG. 21 is an enlarged vertical sectional view depicting the manner in which an egg supported in the compartment a lowermost container is cushioned by the combination of the lid associated with such container and the compartment superimposed thereabove in an adjacent stacked carton or container,

The present invention is directed to a two-piece package for fragile articles such as eggs and the like which includes an elongated compartmented tray section as shown in FIGS. 1-2, and a generally flat cover section 12 as shown in FIGS. 12-15 which may be bonded, mechanically joined or otherwise attached to the tray section. Preferably, the tray section 10 and/or the cover section 12 are formed from a transparent, plastic sheet material such as biaxially oriented polystyrene or the like to enable the ultimate consumer to view the eggs within the package without the necessity of opening it. The transparent character of the tray section 10 and/or cover section 12 coupled with the tamperproof fastening aspects of the present invention, which will be discussed in detail hereinafter, provides a package wherein the articles contained therein may be readily viewed, but access thereto made difiicult except by the positive act of permanently opening the package.

Although the elongated compartmented tray section 10 with the flat cover section 12 is the preferred embodiment of the present invention, it will be apparent, from the ensuing discussion, that the tray and cover section may be either separably or integrally joined to one another with the further alternative that the cover section may comprise an inverted shell which is generally typical with many of the molded fiber cartons, the inverted shell either serving as a cover or additionally having configurations similar to the tray section such that the package has upper and lower cooperating article receiving compartments. All of the above variations are common in the egg package art, and are considered to be within the scope of the present invention.

The elongated compartmented or cellular tray section is preferably formed from a heated web of thermoplastic material such as biaxially oriented polystyrene or the like through the use of thermo-forming techniques which are known in the art. As best illustrated in FIGS. 1-2, the elongated compartmented tray section is generally in the form of a rectangular box-like configuration having an open top with there being two rows of six compartments 14 for receiving fragile articles such as the eggs 16 illustrated in FIG. 1, for example.

Each of the compartments 14 are interconnected to one another along inner margins thereof by the paratition walls 18 which extend between adjacent compartments. The partition walls 18 between each group of four compartments is generally in the form of a cross-pattee 20 which enables each of the compartments to be generally curvilinear in form along the inner margins thereof while being a closely adjacent positions relative to one another. Each of the fingers of the cross-pattee 20 forming the dividing walls or partitions 18 are generally arranged apart from one another and have inwardly curving margins which conform to the exterior or marginal configuration of each of the curvilinear compartments 14. Centrally positioned relative to each of the cross-pattees 20 is an article supporting structure 22 which resists bending of the tray section between the compartments 14 without in any way interfering with the easy removal of articles from the compartments 14. The article supporting structure 22 can also be characterized generally in the shape of a cross-pattee, but having an upwardly dished or domed section which resists bending or twisting of the tray section 10 between the compartments 14. Further, the arrangement of the cross-pattee 22 forming the article supporting structure with the partition walls 18, the latter being supported by the wall portions of the compartments 14 and the surrounding wall structure 22 of the tray section, as will be set forth in detail hereinafter, counteracts fiexing even though the tray section 10 is grasped near one end thereof.

In addition to the plurality of interconnected compartments 14, the tray section 10 includes the surrounding wall structure 22 which is peripherally continuous above the partition walls 18, but is also integrally connected to each of the interconnected compartments 14 along the outer margins thereof as will become apparent. It will be noted that the partition walls 18 are generally located along the median plane between the top and bottom of the tray section 10 as is best shown in FIGS. 8-9. Each of the compartments 14 extend below this median plane while the surrounding wall structure 22, except for the integral connections with the compartments 14, projects upwardly above the median plane for a distance at least equal to the height of eggs or other fragile articles when positioned within the compartments 14. In this way, the side wall structure, which incorporates suitable cushioning elements or shock absorbing means as will be later described, protects the eggs 16 for the full height thereof when the cover section 12 is removed from the tray section while at the same time exposing the eggs 16 for easy removal from the tray section. In this latter connection, it will be noted that each article supporting structure in the form of the cross-pattee 22 does not project a significant distance above the partition walls 18, and thus does not interfere with the removal of the eggs 16 from the tray section.

When the tray section It) fills with eggs 16 has been lifted, for example, at one end thereof, it is important that the weight of the eggs not destroy what is otherwise a stable package. The package must be designed, therefore, to counteract any tendency of the eggs 16 to bend or flex the partition walls 18. The present invention overcomes this tendency by a particular structural arrangement which has been found to be very workable in practice.

As previously indicated, there is provided intermediate each group of four compartments arranged in pairs in the two juxtaposed rows thereof an article supporting means 22 which is smaller than, but generally similar in shape to the cross-pattee 20 which forms the partition walls 19 between each group of four closely adjacent compartments 14. The article supporting means 22 thus derives substantial support from the dividing walls or partitions 18 which are themselves supported in a general axial direction by the curvilinear inner margins of the peripherally continuous side portions 32 of each compartment 14, and also in a general radial direction by the inwardly offset trapezoidally-shaped surfaces 24 and also the briding wall portions 28 thereof which extend generally intermediate the compartments 14 in the plane of the surrounding wall structure or exterior peripherally continuous wall section 23. Further, the article supporting means or structure 22 includes an upwardly dished or domed top section 22a with four inwardly concave side sections 22b which extend in a general axial direction and form extensions of the peripherally continuous surface 32 of each compartment only in the vicinity of the article supporting means 22. The structural cooperation of the various elements just described resist, to a large degree, bending of the tray section 10 between the compartments 14, and thus provides a rigid and stable package which may be handled in a normal manner by the ultimate consumer.

Besides the protection afforded to the eggs 16 by the surrounding wall structure 23 which projects above the median plane of the tray section 10, the tray section 10 also preferably incorporates axial and lateral shock absorbing or cushioning features which will now be described.

Considering first the lateral shock absorbing or cushioning features of the tray section, it will be noted that the surrounding wall structure 23 includes a plurality of inwardly and outwardly offset trapezoidally-shaped or wedge-shaped surfaces 24, 26 which are alternatively inverted with respect to one another to provide a pair of non-parallel edges 24a, 24b for each inwardly offset trapezoidally-shaped surface 24 and a pair of non-parallel edges 26c, 26d for each outwardly offset trapezoidallyshaped surface 26. Each of the non-parallel edges 26c, 26d of an outwardly offset trapezoidally-shaped surface 26 is arranged in aligned relationship with the non-parallel edges 24b, 2411 respectively of adjacent inwardly offset trapezoidally-shaped surfaces 24 located on opposite sides of each outwardly offset trapezoidally-shaped surface 26. Further, the aligned edges 24a, 26a' and 24b, 260 of the inwardly and outwardly offset trapezoidally-shaped surfaces 24, 26 are connected to each other by bridging wall portions 28 which extend substantially normal to each of the trapezoidally-shaped surfaces 24, 26 and thereby provide a rigid side wall structure for the container or tray section 10.

It will be noted that the outwardly offset trapezoidallyshaped surfaces 26 extend between the top and bottom of the tray section, as best seen in FIGS. 89, throughout the entire height thereof, and this, together with the bridging wall portions 28, provides the integral connection between the surrounding wall structure 23 and the compartments 14 along the outer margin or periphery thereof as will be apparent. The inwardly offset trapezoidallyshaped surfaces 24, on the other hand, are generally positioned between adjacent compartments and thus intersects the partition walls 18 generally along the median plane of the tray section 10. The partition walls 18 and the side wall structure 23 are thereby integrally and structurally connected to one another to afford substantial side Wall rigidity for the tray section 10.

At the same time, however, the non-parallel edges 24a, 24b of the inwardly offset trapezoidally-shaped surfaces 24 continue downwardly beneath the median plane of the tray section and intersect the compartment 14 in a manner to be presently described to provide the lateral shock absorbing or cushioning feature previously alluded to.

Each of the compartments 14 includes, as best illustrated in FIGS. 26, a bottom portion 30, preferably of special configuration as will be discussed, and a peripherally continuous side portion 32 which. extends upwardly and outwardly therefrom terminating generally along the median plane of the tray section for integral connection with the partition walls 18- located in that vicinity. It will be recognized, of course, that part of the peripherally continuous side portion 32 of each compartment 14 along the outer margin thereof, constitutes the outwardly offset trapezoidally-shaped surface 26 and the bridging wall portions 28 associated therewith and arranged in the manner illustrated in the drawings.

The non-parallel edges 24a, 24b of each inwardly offset trapezoidally-shaped surface 24 extend, as previously indicated, below the medianplane of the tray section 10 and intersect the peripherally continuous side wall portion surrounding each compartment such that the juncture between the non-parallel edges 24a, 24b of adjacent inwardly offset trapezoidally-shaped surfaces 24 or the extensions of the marginal or bridging wall portions 28 of the outwardly offset trapezoidally-shaped surface 26 associated with a respective compartment 14 and their juncture with the peripherally continuous side wall portion 32 of such compartment will provide a pair of spaced limited surface areas or inside corner portion 34a, 34b which correspond to the extensions of the non-parallel edges 24a, 24b of adjacent inwardly offset trapezoidally-shaped surfaces 24.

Intermediate each pair of spaced limited surface areas or inside corner portions 34a, 34b, there is provided a rib means 35 which extends inwardly from the outwardly offset trapezoidally-shaped surface 26 between the areas or portions 34a, 34b. Each of the spaced limited surface areas or inside corner portions 34a, 34b cooperate with the inwardly extending rib means 36 located intermediate thereof to provide spaced surface contact with articles positioned in the compartments. This is best shown in FIGS. 8-10of the drawings wherein each compartment includes as illustrated, a spaced three point contact which insulates or protects articles positioned in the compartments 14 from lateral forces externally of the package. It will be seen that each of the two outer compartments 14 at opposite ends of the tray section 10 includes first and second pairs of cooperating limited surface areas 34a, 34b and rib means 36 generally arranged at right angles to one another to afford protection to the eggs received in such compartments in two directions.

Since the tray section is preferably thermoformed from a biaxially oriented polystyrene material having a thin wall character (on the order of .004.O34 inch in thickmess), the cooperating limited surface areas 34a, 34b and the rib means 36 of each compartment provides a resilient support for the eggs or other fragile articles positioned within the compartments for limited lateral movement. During shipping, it will be apparent that the partition walls 18 will separate the eggs 16 from one another while the cooperating limited surface areas 34a, 34b and the rib means 36 associated with each compartment supports and protects the eggs against breakage from outside forces or lateral movement. When the cover section 12 has been removed from the tray section 10, the eggs 16 will remain protected by the cooperating limited surface areas 34a, 34b within the compartments 14, and also by the edges 24a, 24b of each inwardly offset trapezoidallyshaped surface 24 which extends above the median plane of the tray section 10 for the maximum height of the eggs 16 when positioned within the compartments 14.

In addition to the lateral shock absorbing or cushioning elements of the tray section 10, there is provided in each of the compartments 14 a specially configured bottom portion which absorbs or cushions axial shock imposed on the tray section which may occur as the result of drop impact forces. This bottom portion 30 and the manner in which it functions to cushion or absorb axial shock forces will be best understood by a reference to FIGS. 3-6 of the drawings.

As shown in FIGS. 3-6, the eggs 16 are received within the compartments 14 usually with the pointed end down. The bottom portion 30 in each compartment 14; which receives and supports the eggs includes an annular supporting surface which is integrally connected along its outermost periphery to the lowermost extremity of the peripherally continuous side portion 32 of each compartment. The innermost margin of each annular supporting surface 40 is integrally joined to a stair stepped supporting structure 42 which is configured to yield in discrete stages when an axial impact force is imposed upon the stair stepped structure. As shown in FIGS. 36 of the drawings, the stair stepped supporting structure 42 preferably includes a single supporting step only, although as illustrated in FIG. 7 of the drawings, a plurality of supporting steps may be provided. Each of the supporting steps includes a lower upwardly and inwardly directed frusto-conical section or rise 44, an upper inwardly and upwardly directed frusto-conical section or rise 46, and a substantially horizontally directed shelf portion 48 of smaller radial width than the axial height of the upper and lower rises 44, 46. The stair stepped supporting structure 42 further includes a centrally positioned well portion 50 having an inwardly sloping wall 52 and a substantially flat bottom wall 54- for receiving the pointed end of an egg 16 as illustrated in FIG. 3 of the drawings. The inwardly sloping wall 52 of the centrally positioned well portion 50 is integrally joined at its upper end to the upper rise 46. The juncture between the inwardly sloping wall 52 and the upper rise 46 provides a circumferentially extending lip portion 56 which is useful in engaging an egg 16 as will become apparent.

FIG. 3 of the drawings illustrates an egg 16 in a static or rest position while FIGS. 4-6 depict various positions of an egg 16 which it encounters in successive stages and which results from the imposition of a drop impact force. When the eggs are in a static condition as illustrated in FIG. 3 of the drawings, the pointed end of each egg 16 is designed to rest against the bottom wall 54 of the centrally positioned well portion 50 with the circumferentially extending lip portion 56, at the juncture of the inwardly sloping wall 52 and the upper rise 46, either positioned in close proximity to or touching the outer curvilinear portion of each egg 16. Thus, the eggs 16 will be confined and centered in the compartments 14 by the circumferentially extending lip portions 56 in each compartment.

When the eggs are subjected to a drop impact force, they will move in the manner illustrated in FIGS. 46 of the drawings with the supporting structure 42 absorbing or cushioning the shock that is imposed on the tray section 10 to protect the eggs from breaking. The first movement that is encountered is illustrated in FIG. 4 of the drawings where the bottom wall 54 deforms curvilinearly to the outer curved shape at the pointed end of each egg 16. If the circumferentially extending lip portion 56 was not in initial engagement with an egg 16, then the deformation of the bottom wall 54 is designed to bring the circumferentially extending lip portion 56 into contacting engagement with the egg. This line contact engagement of each circumferentially extending lip portion 56 with a corresponding egg 16 achieves throughout the various successive stages of movement of the eggs 16, a centering action of the eggs 16 within the compartments 14 which properly positions the eggs 16 for the cushioning or shock absorbtion which is accomplished through the stair stepped supporting structure 42.

As each egg 16 continues its downward movement, the stair stepped supporting structure 42 is designed to collapse in a manner which will permit the upper rise 46 to be telescoped at least partially within the lower rise 44 to provide axial yielding of the stair stepped supporting structure. This is clearly depicted in FIGS. 56 of the drawings, FIG. 5 illustrating the initial telescoping movement of the lower and upper rises 44, 46 of the supporting step, and FIG. 6 showing the final or ultimate telescoping movement of the lower and upper rises 44, 46 of each supporting step. This telescoping movement is achieved as the result of a deflection or bending of the substantially horizontally directed shelf portion 48 as the upper rise 46 is axially moved within the lower rise 44. The lower rise 44 tapers upwardly and inwardly preferably at an angle of approximately 30 degrees from horizontal while the upper rise 46 tapers upwardly and inwardly preferably at an angle of approximately 10 degrees from horizontal, and this specific arrangement is designed to permit telescoping movement of the upper rise 46 into the lower rise 44 while the lower rise 44 is slightly bent at the lowermost position of the stair stepped supporting structure as illustrated in FIG. 6 of the drawings. It is well known that it requires greater force to axially compress a cylindrical section the same distance as a frusto-conical section, all other factors being equal, and the same is true in regard to smaller vs. larger amounts of taper of various frusto-conical sections. Thus, in regard to the lower and upper rises 44, 46, the lower rise 44 having the greater angle will deflect or bend with less load than the upper rise 46, and this is what is intended by the various illustrated movements of the stair stepped supporting structure 42.

It will be noted that each egg 16 is cushioned such that the final or ultimate movement of each egg 16, as viewed in FIG. 6 of the drawings, will terminate before the bottom wall 54 of each centrally positioned well portion 50 is brought into engagement with a supporting surface. This is accomplished by relating the configuration and dimension of the stair stepped supporting structure 42 to the tray section material and its wall thickness to provide adequate yielding of the stair stepped supporting structure, without too early of a collapse thereof, when an axial impact force is imposed on the stair stepped supporting structure. With a tray section made from high impact polystyrene having a wall thickness on the order of .004.034 inch in thickness, the stair stepped supporting structure is configured and dimensioned in the manner illustrated in the drawings to provide absorption of shock or cushioning of each egg 16 to prevent breakage thereof when subject to a drop impact force from a height, for example, of three feet.

It is, of course, possible to utilize a plurality of supporting steps in the stair stepped supporting structure 42 as illustrated in FIG. 7 of the drawings. This, of course, depends on the desired amount of impact force which is to be absorbed in relation to the material of the tray section and its wall thickness. Those skilled in the art will be able to envision the desirability of utilizing a plurality of supporting steps rather than a single supporting step when there is a change in the various factors affecting the amount of force which may be absorbed or cushioned by the stair stepped supporting structure shown in FIGS. 3-6 of the drawings.

In FIGS. 20-21 of the drawings, the stair stepped supporting structure 42 is shown as being useful in conjunction with a plurality of stacked packages. Specifically, it will be noted that the cover section 12, which may be a flexible member, of a subjacent tpackage is capable of yielding axially upwardly into the area defined by the axially upwardly positioned stair stepped supporting structure 42 formed in the compartment 14 of a superimposed package. Since the annular supporting surface 40 of each superimposed container is capable of resting upon and engaging the cover section 12 of a subjacent container, the air cushion created thereby in conjunction with the flexing of the cover section 12 axially upwardly into the space defined by the stair stepped supporting structure 42 will provide a cushion or shock absorbing structure for the eggs 16. It will be recognized that this particular type of axial shock absorbing or cushioning structure is designed to protect only the blunt or upper end of the eggs 16, and only when a plurality of packages are stacked in the manner shown in FIGS. -21. However, this particular aspect may be useful in practicing certain forms of the present invention.

As indicated in FIG. 11 of the drawings, a plurality of similarly configured tray sections 10 may be stacked one within the other with the stacking means 38 in engagement with one another and preventing complete telescopic association between adjacent nested tray sections. Each stacking means includes, from bottom to top, a lower substantially horizontally directed stacking shelf 38a, an upwardly and inwardly inclined intermediate section 38b, and a generally horizontally directed upper stacking shelf 380. As will be apparent from an inspection of FIG. 11 of the drawings, the lower stacking shelf 38a of each superimposed container is adapted to rest upon the upper stacking shelf 380 of a subjacent container with the intermediate sections 38b providing more than a material thickness overlap and capable of yielding axially, when the tray section is made from thin wall plastic material, to prevent jamming between adjacent containers.

It will be noted that each of the stacking means 38 is illustrated as being incorporated within the generally wedge-shaped or outwardly offset trapezoidally-shaped surface 26 associated with each compartment 14, and this has the advantage that adjacent tray sections 10 to be nested together can be guided and centered by the wedge-shaped or outwardly offset trapezoidally-shaped surfaces 26 and the bridging walls 28 throughout substan tially the entire height of the tray sections 10.

To permit nesting between adjacent tray sections 10, it will be apparent that the peripherally continuous side portion 32 of each compartment 14 as well as all of the various elements of the surrounding wall structure 23 including the inwardly and outwardly offset trapezoidallyshaped surfaces 24, 26 and the bridging wall portions 28 extend upwardly and outwardly from the bottom to the top of each tray section. Further, to permit alignment and centering of adjacent tray sections 10 as they are nested one within the other, the bridging wall portions 28 also taper upwardly and outwardly from the bottom to the top of each tray section. As a result, adjacent nested tray sections 10 can be quickly and easily nested or separated from one another in controlled fashion, and when nested, are stacked apart from one another by the stacking means 38 which prevents complete telescopic association of adjacent nested containers which could cause jamming therebetween and consequent difliculty in separation.

Reference is now made to FIGS. 1 2-16 which illustrates the manner in which the tray section 10 and its associated cover section 12 may be secured to one another. In FIGS. 12-13, a mechanical fastening technique is employed, whereas in FIGS. 14-15, an adhesive technique such as heat sealing or bonding is employed.

The mechanical fastening technique illustrated in FIGS. 12'-13 relates to the provision of a plurality of spaced, integral hollow projections 60 which are formed in the rim portion 62 at the upper end of each tray section. Each of the integral hollow projections 60 preferably project upwardly from a bridging top surface 66 integrally connecting the bridging wall portions 28 on opposite sides of each inwardly offset trapezoidally-shaped surface 24 with the rim portion 62 although they may be located anywhere in the rim portion 62 and with any suitable spacing therebetween as may be desired. Each of the projections 60 are adapted to be received by complementary apertures 68 formed in the cover section 12. Once the integral projections 60 are so positioned within the complementary apertures 68 of the cover section 12, the projections 60 can then be crushed because of their configuration and dimension relative to the complementary apertures 68 of the cover section. Specifically, each of the projections 60 are configured and dimensioned relative to the complementary apertaures 68 such that axial compression thereof will, upon crushing the projections 60) to a position beyond the elastic limit of the material, provide anenlarged permanently deformed head 70 as shown in FIG. 13 at the free end of each projection 60 which has a transverse dimension greater than a corresponding complementary aperture to permit the initial assembly and retention of the tray section 10 and cover section 12 to each other. However, because the cover section 1.2 is preferably a flexible and peelable element, the ultimate consumer may grasp the outer margin of the cover section and manually strip the cover section 12 from the tray section 10 without great difliculty. This mechanical fastening technique in the tray and cover section environment provides a tamperproof package which, together with the transparent aspects of the tray and/or cover section, provides a package wherein the contents thereof are visible, but making it diflicult to gain access to the contents of the package without leaving it in an open condition.

FIGS. 14-15 show that it is also possible to join the tray section 10 and cover section 12 by adhesive techniques such as bonding or heat sealing or the like which provides tamperproof features in a transparent package. Preferably, bonding or heat sealing techniques are used in view of the preferred choice of utilizing thermoplastic material in the tray section 10' and cover section 12. As will be apparent, the cover section 12 along the outer margins thereof may be heat sealed to the tray section rim portion 62 by suitable bonding and heat sealing techniques which are known in the art. It is desirable, particularly when using this form of the invention, that outer peripheral marginal portions 72 be left attached or otherwise secured to the rim portion 62 of a corresponding tray section as this will enhance the lateral rigidifying characteristics of the tray section 10 when the cover section 12 is removed therefrom to permit exposure to theleggs 16 contained within the tray section 10. As illustrated in FIG. 16 of the drawings, this is preferably accomplished by providing a perforated impression or. score line 74 in the cover section 12 at a location just slightly radially inwardly of the rim portion 62 of the traysection 10 when the cover section 12 is secured thereto. The perforated impression or score line 74 extends circumferentially around the tray section except at one or more of the corner portions 76 where a complete slit is provided as a convenient location to grasp the portions of the cover section 12 located radially inwardly of the perforated impression or score line 74, for removing these portions from the tray section 10. It will be apparent that other types of tear tabs may be provided in accomplishing what is intended to be achieved by the structural cooperation of the elements just described.

Reference is now made to FIGS. 17-19 for a discussion of the manner in which the tray section 10 may be designed to be radially collapsed. As previously indicated, each tray section 10 is preferably of the nestable variety, and this necessitates an upward and outward taper for the compartments 14 and the surrounding side wall structure 23 of the tray section. In certain cases, the amount of upward and outward tapering may affect the ability of the package to be packed in suitable cartons or cases for transporting to the ultimate consumer. As a result, it has been found very desirable to provide a radial collapsing feature in the tray section 10 such that the width thereof is kept within prescribed limits to readily fit within existing cartons or cases presently being used. Further, the collapsing feature has the advantage that it may be utilized with the cover section 12 in maintaining it in a taunt or tensioned condition to prevent any wrinkles or creases therein.

As shown in FIG. 17, the tray section is provided, at each end thereof, with an outwardly opening notch means 78 which is located within and generally complementary to the inwardly offset trapezoidally-shaped surface 24 centrally positioned at each end of the tray section 10. Each of the notch means 78 in the rim portion 62 of a tray section 10 permit radial inward movement or collapse of the sides of the tray section 10 from the dotted to the full line position illustrated in FIGS. 18-19 of the drawings. The inward movement or collapse of the sides of the tray section 10 is sufficient to permit egg packages to be stored in cartons or cases currently being used for transport to the ultimate consumer. The cover section 12 is attached or joined to the rim portion 62 of the tray section 10 after the inward movement or collapse of the tray section 10 and when secured, is maintained in a taut or tensioned condition as the result of the notch means 78 tending to return to its initial or open position. Accordingly, the cover section 12 will be substantially devoid of any wrinkles or creases.

From the foregoing, it will now be appreciated that the present invention contemplates a novel package for fragile articles incorporating several radical departures from prior art efforts which have resulted in a much improved package for the manufacturer, egg processor, grocery store owner and ultimate consumer.

I claim:

1. A container for fragile articles comprising an elongated compartmented tray section and a cover section, said tray section including a plurality of interconnected compartments and a surrounding wall structure, the surrounding wall structure including a channel-shaped, inwardly opening pocket for each of said compartments which is defined by a pair of spaced marginal surfaces and a connecting surface therebetween, each pair of said marginal surfaces intersecting a respective compartment and being outwardly directed with respect thereto, the juncture between each marginal surface and the surrounding wall structure adjacent each pocket providing a limited surface area for engaging articles positioned within said compartments, and rib means extending inwardly from the connecting surface of each pocket at a location generally intermediate each pair of marginal surfaces for engaging articles positioned within said compartments, whereby the limited surface area of each pair of marginal surfaces and said rib means intermediate thereof cooperate to provide spaced surface contact of the surrounding wall structure with articles positioned in said compartments.

2. A container as defined in claim 1 wherein the cover section also comprises a compartmented section constructed in the same manner and adapted to engage fragile articles in the same way as said elongated compartmented tray section.

3. The container as defined in claim 1 wherein the container is made from a material enabling each pair of cooperating limited surface areas and the rib means intermediate thereof to resiliently support the articles contained in the compartments for limited lateral movement.

4. The container as defined in claim 1 wherein each of the compartments at each end of the elongated compartmented tray section includes a pair of channel-shaped, inwardly opening pockets arranged generally at right angles to each other, each pair of limited surface areas and the rib means associated therewith in each pocket providing a spaced surface contact of the surrounding wall structure with articles positioned in said compartments.

5. A plastic container for fragile articles including a compartmented tray section of resilient thin wall plastic material having a plurality of interconnected compartments which are configured complementary to the fragile articles to be received therein, each of said compartments having a bottom portion incorporating cushion means which absorbs axial impact forces, said cushion means comprising a centrally positioned well portion which is axially positioned upwardly from the lowermost extent of the compartment by a stair stepped supporting structure having at least one step including an upper rise, a lower rise, and a substantially horizontally extending shelf extending therebetween which connects the upper extremity of the lower rise with the lower extremity of the upper rise, each step in the stair stepped supporting structure being configured and dimensioned relative to the tray section material and its thickness to cause telescoping movement of its upper rise into its lower rise and consequent yielding of said stair stepped supporting structure when an axial impact force is imposed thereon.

6. The plastic container as defined in claim 5 including a cover section which is constructed in the same manner and is adapted to engage fragile articles in the same way as said tray section.

7. The plastic container as defined in claim 5 wherein the lowermost step in the stair stepped structure yields axially when the axial impact load is imposed thereon until it is brought into engagement with the surface against which the container comes into contact, and each next upwardly adjacent step yields axially until the force imposed thereon exceeds its resilient supporting limit.

8. The plastic container as defined in claim 5 wherein each centrally positioned well portion includes a circumferentially extending lip portion at the uppermost extremity thereof which is configured relative to articles positioned in said compartments to provide line contact engagement therewith.

9. The plastic container as defined in claim 8 wherein each lip portion of a centrally positioned well portion engages an article positioned within a respective compartment only after the imposition of an axial impact load.

10. The plastic container as defined in claim 5 wherein the upper and lower rise of each step in the stair stepped supporting structure comprises an upwardly and inwardly inclined frusto-conical portion.

11. The plastic container as defined in claim 10 wherein the stair stepped supporting structure comprises a single step having the uppermost frusto-conical portion thereof tapering upwardly and inwardly at an angle less than the lowermost frusto-conical portion.

12. A plastic container for fragile articles including a compartmented tray section and a cover section, said tray section including a plurality of interconnected compartments and a surrounding wall structure which terminates at its upper end in a rim portion, said cover section comprising a flexible, substantially flat panel member which is secured to the rim portion of the elongated cellular tray section, each of the compartments having a bottom portion incorporating cushion means which absorbs axial impact forces of fragile articles received therein, said cushion means being axially positioned upwardly from an annular supporting surface of the compartment bottom portion and being adapted to rest upon the flat panel member of a subjacent plastic container whereby the area of the flat panel member confined by the annular supporting surface of a superimposed container is capable of yielding axially upwardly into the area defined by the axially upwardly positioned cushion means formed in the compartments of a superimposed container for absorbing axial impact forces.

13. A plastic egg carton including an elongated compartmented tray section and a cover section therefor, said tray section being sheet formed from a thermoplastic web and having a plurality of compartments which are interconnected to each other by dividing portions located generally along the median plane of the tray section, each of said compartment below the median plane of the tray section having a bottom portion and a peripherally continuous side portion which extends upwardly and outwardly therefrom and is joined to the dividing portions along inner margins between adjacent compartments, each of said compartments above the median plane having an exterior peripherally continuous wall section surrounding all of said erally continuous wall section surrounding all of said compartments and projecting upwardly and outwardly from the median plane by a distance greater than the maximum height of eggs when positioned in said compartments, said peripherally continuous exterior side wall surface terminating in a rim portion to which said cover section is adapted to be secured, each of the compartments and dividing portions within the exterior peripherally continuous wall section extending upwardly no further than the median plane of the tray section to facilitate grasping of eggs positioned in said compartments.

14. A plastic egg carton as defined in claim 13 wherein said exterior peripherally continuous wall section is configured for inward collapse thereof to reduce the overall dimensions of the trap section in the vicinity of said outer peripherally continuous side wall surface.

15. A plastic egg carton as defined in claim 14 wherein said tray section includes notch means provided in the rim portion thereof at opposite ends of the tray section to cause inward collapse of the tray section.=

16. A plastic egg carton as defined in claim 15 including means for retaining the exterior peripherally continuous wall section of the tray section in a collapsed condition. 1

17. A plastic egg carton as defined in claim 16 wherein said last mentioned means comprises said cover section, the exterior peripherally continuous Wall section of the tray section tending to return to its non-collapsed position and thereby holding said cover section in a taut condition.

18. A plastic egg carton as defined in claim 17 wherein said cover section includes means for removing all but the outermost peripheral margin of the cover section to permit exposure to the contents of the carton.

19. A plastic egg carton as defined in claim 18 wherein said last mentioned means includes a perforated impression in the cover section extending in a circumferential manner around the tray section and located inwardly of the rim portion thereof.

20. A plastic egg carton as defined in claim 13 wherein each of said compartments includes lateral shock absorbing means.

21. A plastic egg carton as defined in claim 20 wherein each of said compartmtnts also includes axial shock absorbing means.

22. The supporting tray as defined in claim 18 and including a peripherally continuous exterior side wall surface surrounding each of said compartments and extending upwardly therefrom for a distance at least as great as the maximum height of eggs when positioned within said compartments, each of said wedge-shaped lead-in portions extending throughout the entire axial height of the peripherally continuous exterior side wall surface surrounding each of said compartments and extending thereabove.

References Cited UNITED STATES PATENTS 1,990,145 2/1935 Swift 229-29 XR 2,047,495 7/ 1936 Schurmann 229-28 2,160,893 6/1939 Nelson 229-29 2,873,057 2/1959 Friday 229-2.5 2,974,842 3/1961 Reifers 2292.5 3,091,360 5/1963 Edwards 220-97 3,129,866 4/1964 Wade 2292.5 3,139,213 6/1964 Edwards 220-97 3,217,961 11/1965 Hornbostel 2292.5 3,262,632 7/1966 Brady et al. 229-51 3,334,765 8/1967 Modersohn 229-2.5 3,375,966 4/1968 Crabtree 229-2.5 3,000,528 9/1961 Kuhl et a1. 217-265 3,131,846 5/1964 Whiteford 229-2.5 3,162,352 12/1964 Swain 2129-54 3,288,323 11/1966 Schechter 220-54 U.S. C1. X.R. 229-29 

